1. Field of the Invention
The present invention relates to a bracket to be used exclusively for fixing a flexible tube, such as the protective boot installed in an automobile suspension device, to a prescribed member.
2. Description of the Prior Art
Automobile suspension devices come in several types, one of which is a strut type automobile suspension device.
A suspension device of the strut type, not specifically shown herein, but disclosed in Japanese Patent Public Disclosure No. 63-199108, is so constructed that a lower receiving plate is fixed to an upper terminal part of a dumper case, an upper receiving plate is rotatably disposed on the upper terminal part of a piston rod adapted to slide inside the dumper case, a compression coil spring is interposed between the upper and lower receiving plates, a protective boot made of rubber is wrapped around the projected periphery of the piston rod, and the upper terminal part of the protective boot is fixed at the upper receiving plate. Thus, impacts and vibrations exerted by the road surface upon a tire are absorbed by the actions of the compression coil spring and the dumper and are prevented from being directly transmitted to the automobile body.
In the automobile suspension device of the conventional strut type constructed as described above, however, the protective boot is fixed at the upper terminal part thereof to the upper receiving plate, and is not fixed, but left free, at the lower terminal part thereof.
When dirt, dust, etc. are hurled up from the road surface by the tire while the automobile is in motion, and are then suffered to reach the sealed surfaces of the dumper case and the piston rod via the open area in the lower terminal part of the protective boot, eventually adhering to the peripheral surface of the piston rod, there is a fair possibility of the dirt, dust, etc inflicting injury on the sealed surfaces as a consequence of the sliding motion of the piston rod.
In the suspension device of the strut type, therefore, the protective boot is required to be additionally fixed at the lower terminal part thereof to the upper end of the dumper case and consequently to be allowed to close the open region so as to protect the sealed surfaces against dirt, dust, etc.
In the suspension device of the strut type, however, for the absorption of the impacts and vibrations transmitted from the road surface, the compression coil spring is expanded or contracted proportionately to the sliding motion of the piston rod inside the dumper case to allow the wheel to move vertically. At this time, owing to the structural characteristics the compression coil spring is suffered to twist and, as a result, the upper receiving plate supporting the compression coil spring thereon is synchronously rotated in the same direction.
When the protective boot, in light of this structural characteristic, is so constructed as to be fixed not only on the upper terminal part but also on the lower terminal part, then as a consequence of the fixation on the lower terminal part, the rotation of the upper receiving plate, synchronized with the twisting of the compression coil spring, causes the upper terminal part of the protective boot fixed to the upper receiving plate to be automatically twisted in the same direction. Thus, there arises the possibility that the upper terminal part of the protective boot will fatigue and break owing to the twist of the upper terminal part of the protective boot.
By merely fixing the protective boot at the lower terminal part thereof, therefore, the peripheral surface of the piston rod cannot be effectively protected against dirt, dust, etc. because of the fatigue and breakage of the upper terminal part of the protective boot. In the field pertinent to this invention, therefore, the debut of a novel fixing means capable of effectively preventing the upper terminal part of the protective boot from being twisted in spite of the fixation of the protective boot at the lower terminal part thereof has been greatly longed for.
Accordingly, the primary object of the present invention, which has been developed to fulfill the above demand, is to provide a novel fixing bracket which prevents the terminal parts of a flexible tube from being twisted in consequence of the rotation of a pertinent member and precludes the possibility of the terminal parts of the flexible tube being broken through fatigue.